6 files changed, 140 insertions, 176 deletions

diff --git a/drivers/md/bcache/bcache.h b/drivers/md/bcache/bcache.h
index 166c8ddc0be4..ad4957b52f10 100644
--- a/drivers/md/bcache/bcache.h
+++ b/drivers/md/bcache/bcache.h
@@ -819,10 +819,9 @@ struct cache_set {
 
         /*
          * A btree node on disk could have too many bsets for an iterator to fit
-         * on the stack - this is a single element mempool for btree_read_work()
+         * on the stack - have to dynamically allocate them
          */
-        struct mutex            fill_lock;
-        struct btree_iter       *fill_iter;
+        mempool_t               *fill_iter;
 
         /*
          * btree_sort() is a merge sort and requires temporary space - single
diff --git a/drivers/md/bcache/btree.c b/drivers/md/bcache/btree.c
index 45b88fbffbe0..aaec186f7ba6 100644
--- a/drivers/md/bcache/btree.c
+++ b/drivers/md/bcache/btree.c
@@ -134,44 +134,17 @@ static uint64_t btree_csum_set(struct btree *b, struct bset *i)
         return crc ^ 0xffffffffffffffffULL;
 }
 
-static void btree_bio_endio(struct bio *bio, int error)
+void bch_btree_node_read_done(struct btree *b)
 {
-        struct closure *cl = bio->bi_private;
-        struct btree *b = container_of(cl, struct btree, io.cl);
-
-        if (error)
-                set_btree_node_io_error(b);
-
-        bch_bbio_count_io_errors(b->c, bio, error, (bio->bi_rw & WRITE)
-                                 ? "writing btree" : "reading btree");
-        closure_put(cl);
-}
-
-static void btree_bio_init(struct btree *b)
-{
-        BUG_ON(b->bio);
-        b->bio = bch_bbio_alloc(b->c);
-
-        b->bio->bi_end_io       = btree_bio_endio;
-        b->bio->bi_private      = &b->io.cl;
-}
-
-void bch_btree_read_done(struct closure *cl)
-{
-        struct btree *b = container_of(cl, struct btree, io.cl);
-        struct bset *i = b->sets[0].data;
-        struct btree_iter *iter = b->c->fill_iter;
         const char *err = "bad btree header";
-        BUG_ON(b->nsets || b->written);
-
-        bch_bbio_free(b->bio, b->c);
-        b->bio = NULL;
+        struct bset *i = b->sets[0].data;
+        struct btree_iter *iter;
 
-        mutex_lock(&b->c->fill_lock);
+        iter = mempool_alloc(b->c->fill_iter, GFP_NOWAIT);
+        iter->size = b->c->sb.bucket_size / b->c->sb.block_size;
         iter->used = 0;
 
-        if (btree_node_io_error(b) ||
-            !i->seq)
+        if (!i->seq)
                 goto err;
 
         for (;
@@ -228,17 +201,8 @@ void bch_btree_read_done(struct closure *cl)
         if (b->written < btree_blocks(b))
                 bch_bset_init_next(b);
 out:
-
-        mutex_unlock(&b->c->fill_lock);
-
-        spin_lock(&b->c->btree_read_time_lock);
-        bch_time_stats_update(&b->c->btree_read_time, b->io_start_time);
-        spin_unlock(&b->c->btree_read_time_lock);
-
-        smp_wmb(); /* read_done is our write lock */
-        set_btree_node_read_done(b);
-
-        closure_return(cl);
+        mempool_free(iter, b->c->fill_iter);
+        return;
 err:
         set_btree_node_io_error(b);
         bch_cache_set_error(b->c, "%s at bucket %zu, block %zu, %u keys",
@@ -247,26 +211,51 @@ err:
         goto out;
 }
 
-void bch_btree_read(struct btree *b)
+static void btree_node_read_endio(struct bio *bio, int error)
 {
-        BUG_ON(b->nsets || b->written);
+        struct closure *cl = bio->bi_private;
+        closure_put(cl);
+}
 
-        if (!closure_trylock(&b->io.cl, &b->c->cl))
-                BUG();
+void bch_btree_node_read(struct btree *b)
+{
+        uint64_t start_time = local_clock();
+        struct closure cl;
+        struct bio *bio;
 
-        b->io_start_time = local_clock();
+        closure_init_stack(&cl);
+        pr_debug("%s", pbtree(b));
 
-        btree_bio_init(b);
-        b->bio->bi_rw   = REQ_META|READ_SYNC;
-        b->bio->bi_size = KEY_SIZE(&b->key) << 9;
+        bio = bch_bbio_alloc(b->c);
+        bio->bi_rw      = REQ_META|READ_SYNC;
+        bio->bi_size    = KEY_SIZE(&b->key) << 9;
+        bio->bi_end_io  = btree_node_read_endio;
+        bio->bi_private = &cl;
 
-        bch_bio_map(b->bio, b->sets[0].data);
+        bch_bio_map(bio, b->sets[0].data);
 
-        pr_debug("%s", pbtree(b));
-        trace_bcache_btree_read(b->bio);
-        bch_submit_bbio(b->bio, b->c, &b->key, 0);
+        trace_bcache_btree_read(bio);
+        bch_submit_bbio(bio, b->c, &b->key, 0);
+        closure_sync(&cl);
 
-        continue_at(&b->io.cl, bch_btree_read_done, system_wq);
+        if (!test_bit(BIO_UPTODATE, &bio->bi_flags))
+                set_btree_node_io_error(b);
+
+        bch_bbio_free(bio, b->c);
+
+        if (btree_node_io_error(b))
+                goto err;
+
+        bch_btree_node_read_done(b);
+
+        spin_lock(&b->c->btree_read_time_lock);
+        bch_time_stats_update(&b->c->btree_read_time, start_time);
+        spin_unlock(&b->c->btree_read_time_lock);
+
+        return;
+err:
+        bch_cache_set_error(b->c, "io error reading bucket %lu",
+                            PTR_BUCKET_NR(b->c, &b->key, 0));
 }
 
 static void btree_complete_write(struct btree *b, struct btree_write *w)
@@ -280,15 +269,11 @@ static void btree_complete_write(struct btree *b, struct btree_write *w)
                 __closure_wake_up(&b->c->journal.wait);
         }
 
-        if (w->owner)
-                closure_put(w->owner);
-
         w->prio_blocked = 0;
         w->journal      = NULL;
-        w->owner        = NULL;
 }
 
-static void __btree_write_done(struct closure *cl)
+static void __btree_node_write_done(struct closure *cl)
 {
         struct btree *b = container_of(cl, struct btree, io.cl);
         struct btree_write *w = btree_prev_write(b);
@@ -304,7 +289,7 @@ static void __btree_write_done(struct closure *cl)
         closure_return(cl);
 }
 
-static void btree_write_done(struct closure *cl)
+static void btree_node_write_done(struct closure *cl)
 {
         struct btree *b = container_of(cl, struct btree, io.cl);
         struct bio_vec *bv;
@@ -313,10 +298,22 @@ static void btree_write_done(struct closure *cl)
         __bio_for_each_segment(bv, b->bio, n, 0)
                 __free_page(bv->bv_page);
 
-        __btree_write_done(cl);
+        __btree_node_write_done(cl);
 }
 
-static void do_btree_write(struct btree *b)
+static void btree_node_write_endio(struct bio *bio, int error)
+{
+        struct closure *cl = bio->bi_private;
+        struct btree *b = container_of(cl, struct btree, io.cl);
+
+        if (error)
+                set_btree_node_io_error(b);
+
+        bch_bbio_count_io_errors(b->c, bio, error, "writing btree");
+        closure_put(cl);
+}
+
+static void do_btree_node_write(struct btree *b)
 {
         struct closure *cl = &b->io.cl;
         struct bset *i = b->sets[b->nsets].data;
@@ -325,7 +322,11 @@ static void do_btree_write(struct btree *b)
         i->version      = BCACHE_BSET_VERSION;
         i->csum         = btree_csum_set(b, i);
 
-        btree_bio_init(b);
+        BUG_ON(b->bio);
+        b->bio = bch_bbio_alloc(b->c);
+
+        b->bio->bi_end_io       = btree_node_write_endio;
+        b->bio->bi_private      = &b->io.cl;
         b->bio->bi_rw   = REQ_META|WRITE_SYNC;
         b->bio->bi_size = set_blocks(i, b->c) * block_bytes(b->c);
         bch_bio_map(b->bio, i);
@@ -345,7 +346,7 @@ static void do_btree_write(struct btree *b)
                 trace_bcache_btree_write(b->bio);
                 bch_submit_bbio(b->bio, b->c, &k.key, 0);
 
-                continue_at(cl, btree_write_done, NULL);
+                continue_at(cl, btree_node_write_done, NULL);
         } else {
                 b->bio->bi_vcnt = 0;
                 bch_bio_map(b->bio, i);
@@ -354,26 +355,30 @@ static void do_btree_write(struct btree *b)
                 bch_submit_bbio(b->bio, b->c, &k.key, 0);
 
                 closure_sync(cl);
-                __btree_write_done(cl);
+                __btree_node_write_done(cl);
         }
 }
 
-static void __btree_write(struct btree *b)
+void bch_btree_node_write(struct btree *b, struct closure *parent)
 {
         struct bset *i = b->sets[b->nsets].data;
 
         BUG_ON(current->bio_list);
+        BUG_ON(b->written >= btree_blocks(b));
+        BUG_ON(b->written && !i->keys);
+        BUG_ON(b->sets->data->seq != i->seq);
 
-        closure_lock(&b->io, &b->c->cl);
         cancel_delayed_work(&b->work);
 
+        /* If caller isn't waiting for write, parent refcount is cache set */
+        closure_lock(&b->io, parent ?: &b->c->cl);
+
         clear_bit(BTREE_NODE_dirty,      &b->flags);
         change_bit(BTREE_NODE_write_idx, &b->flags);
 
         bch_check_key_order(b, i);
-        BUG_ON(b->written && !i->keys);
 
-        do_btree_write(b);
+        do_btree_node_write(b);
 
         pr_debug("%s block %i keys %i", pbtree(b), b->written, i->keys);
 
@@ -387,37 +392,31 @@ static void __btree_write(struct btree *b)
                 bch_bset_init_next(b);
 }
 
-static void btree_write_work(struct work_struct *w)
+static void btree_node_write_work(struct work_struct *w)
 {
         struct btree *b = container_of(to_delayed_work(w), struct btree, work);
 
-        down_write(&b->lock);
+        rw_lock(true, b, b->level);
 
         if (btree_node_dirty(b))
-                __btree_write(b);
-        up_write(&b->lock);
+                bch_btree_node_write(b, NULL);
+        rw_unlock(true, b);
 }
 
-void bch_btree_write(struct btree *b, bool now, struct btree_op *op)
+static void bch_btree_leaf_dirty(struct btree *b, struct btree_op *op)
 {
         struct bset *i = b->sets[b->nsets].data;
         struct btree_write *w = btree_current_write(b);
 
-        BUG_ON(b->written &&
-               (b->written >= btree_blocks(b) ||
-                i->seq != b->sets[0].data->seq ||
-                !i->keys));
+        BUG_ON(!b->written);
+        BUG_ON(!i->keys);
 
-        if (!btree_node_dirty(b)) {
-                set_btree_node_dirty(b);
-                queue_delayed_work(btree_io_wq, &b->work,
-                                   msecs_to_jiffies(30000));
-        }
+        if (!btree_node_dirty(b))
+                queue_delayed_work(btree_io_wq, &b->work, 30 * HZ);
 
-        w->prio_blocked += b->prio_blocked;
-        b->prio_blocked = 0;
+        set_btree_node_dirty(b);
 
-        if (op && op->journal && !b->level) {
+        if (op && op->journal) {
                 if (w->journal &&
                     journal_pin_cmp(b->c, w, op)) {
                         atomic_dec_bug(w->journal);
@@ -430,23 +429,10 @@ void bch_btree_write(struct btree *b, bool now, struct btree_op *op)
                 }
         }
 
-        if (current->bio_list)
-                return;
-
         /* Force write if set is too big */
-        if (now ||
-            b->level ||
-            set_bytes(i) > PAGE_SIZE - 48) {
-                if (op && now) {
-                        /* Must wait on multiple writes */
-                        BUG_ON(w->owner);
-                        w->owner = &op->cl;
-                        closure_get(&op->cl);
-                }
-
-                __btree_write(b);
-        }
-        BUG_ON(!b->written);
+        if (set_bytes(i) > PAGE_SIZE - 48 &&
+            !current->bio_list)
+                bch_btree_node_write(b, NULL);
 }
 
 /*
@@ -559,7 +545,7 @@ static struct btree *mca_bucket_alloc(struct cache_set *c,
         init_rwsem(&b->lock);
         lockdep_set_novalidate_class(&b->lock);
         INIT_LIST_HEAD(&b->list);
-        INIT_DELAYED_WORK(&b->work, btree_write_work);
+        INIT_DELAYED_WORK(&b->work, btree_node_write_work);
         b->c = c;
         closure_init_unlocked(&b->io);
 
@@ -582,7 +568,7 @@ static int mca_reap(struct btree *b, struct closure *cl, unsigned min_order)
         BUG_ON(btree_node_dirty(b) && !b->sets[0].data);
 
         if (cl && btree_node_dirty(b))
-                bch_btree_write(b, true, NULL);
+                bch_btree_node_write(b, NULL);
 
         if (cl)
                 closure_wait_event_async(&b->io.wait, cl,
@@ -905,6 +891,9 @@ retry:
         b = mca_find(c, k);
 
         if (!b) {
+                if (current->bio_list)
+                        return ERR_PTR(-EAGAIN);
+
                 mutex_lock(&c->bucket_lock);
                 b = mca_alloc(c, k, level, &op->cl);
                 mutex_unlock(&c->bucket_lock);
@@ -914,7 +903,7 @@ retry:
                 if (IS_ERR(b))
                         return b;
 
-                bch_btree_read(b);
+                bch_btree_node_read(b);
 
                 if (!write)
                         downgrade_write(&b->lock);
@@ -937,15 +926,12 @@ retry:
         for (; i <= b->nsets; i++)
                 prefetch(b->sets[i].data);
 
-        if (!closure_wait_event(&b->io.wait, &op->cl,
-                                btree_node_read_done(b))) {
-                rw_unlock(write, b);
-                b = ERR_PTR(-EAGAIN);
-        } else if (btree_node_io_error(b)) {
+        if (btree_node_io_error(b)) {
                 rw_unlock(write, b);
-                b = ERR_PTR(-EIO);
-        } else
-                BUG_ON(!b->written);
+                return ERR_PTR(-EIO);
+        }
+
+        BUG_ON(!b->written);
 
         return b;
 }
@@ -959,7 +945,7 @@ static void btree_node_prefetch(struct cache_set *c, struct bkey *k, int level)
         mutex_unlock(&c->bucket_lock);
 
         if (!IS_ERR_OR_NULL(b)) {
-                bch_btree_read(b);
+                bch_btree_node_read(b);
                 rw_unlock(true, b);
         }
 }
@@ -982,12 +968,6 @@ static void btree_node_free(struct btree *b, struct btree_op *op)
                 btree_complete_write(b, btree_current_write(b));
         clear_bit(BTREE_NODE_dirty, &b->flags);
 
-        if (b->prio_blocked &&
-            !atomic_sub_return(b->prio_blocked, &b->c->prio_blocked))
-                wake_up_allocators(b->c);
-
-        b->prio_blocked = 0;
-
         cancel_delayed_work(&b->work);
 
         mutex_lock(&b->c->bucket_lock);
@@ -1028,7 +1008,6 @@ retry:
                 goto retry;
         }
 
-        set_btree_node_read_done(b);
         b->accessed = 1;
         bch_bset_init_next(b);
 
@@ -1166,14 +1145,11 @@ static struct btree *btree_gc_alloc(struct btree *b, struct bkey *k,
 
         if (!IS_ERR_OR_NULL(n)) {
                 swap(b, n);
+                __bkey_put(b->c, &b->key);
 
                 memcpy(k->ptr, b->key.ptr,
                        sizeof(uint64_t) * KEY_PTRS(&b->key));
 
-                __bkey_put(b->c, &b->key);
-                atomic_inc(&b->c->prio_blocked);
-                b->prio_blocked++;
-
                 btree_node_free(n, op);
                 up_write(&n->lock);
         }
@@ -1293,14 +1269,9 @@ static int btree_gc_recurse(struct btree *b, struct btree_op *op,
         void write(struct btree *r)
         {
                 if (!r->written)
-                        bch_btree_write(r, true, op);
-                else if (btree_node_dirty(r)) {
-                        BUG_ON(btree_current_write(r)->owner);
-                        btree_current_write(r)->owner = writes;
-                        closure_get(writes);
-
-                        bch_btree_write(r, true, NULL);
-                }
+                        bch_btree_node_write(r, &op->cl);
+                else if (btree_node_dirty(r))
+                        bch_btree_node_write(r, writes);
 
                 up_write(&r->lock);
         }
@@ -1386,9 +1357,7 @@ static int bch_btree_gc_root(struct btree *b, struct btree_op *op,
                 ret = btree_gc_recurse(b, op, writes, gc);
 
         if (!b->written || btree_node_dirty(b)) {
-                atomic_inc(&b->c->prio_blocked);
-                b->prio_blocked++;
-                bch_btree_write(b, true, n ? op : NULL);
+                bch_btree_node_write(b, n ? &op->cl : NULL);
         }
 
         if (!IS_ERR_OR_NULL(n)) {
@@ -1508,8 +1477,8 @@ static void bch_btree_gc(struct closure *cl)
         struct gc_stat stats;
         struct closure writes;
         struct btree_op op;
-
         uint64_t start_time = local_clock();
+
         trace_bcache_gc_start(c->sb.set_uuid);
         blktrace_msg_all(c, "Starting gc");
 
@@ -1520,6 +1489,8 @@ static void bch_btree_gc(struct closure *cl)
 
         btree_gc_start(c);
 
+        atomic_inc(&c->prio_blocked);
+
         ret = btree_root(gc_root, c, &op, &writes, &stats);
         closure_sync(&op.cl);
         closure_sync(&writes);
@@ -1537,6 +1508,9 @@ static void bch_btree_gc(struct closure *cl)
 
         available = bch_btree_gc_finish(c);
 
+        atomic_dec(&c->prio_blocked);
+        wake_up_allocators(c);
+
         bch_time_stats_update(&c->btree_gc_time, start_time);
 
         stats.key_bytes *= sizeof(uint64_t);
@@ -1544,10 +1518,9 @@ static void bch_btree_gc(struct closure *cl)
         stats.data      <<= 9;
         stats.in_use    = (c->nbuckets - available) * 100 / c->nbuckets;
         memcpy(&c->gc_stats, &stats, sizeof(struct gc_stat));
-        blktrace_msg_all(c, "Finished gc");
 
+        blktrace_msg_all(c, "Finished gc");
         trace_bcache_gc_end(c->sb.set_uuid);
-        wake_up_allocators(c);
 
         continue_at(cl, bch_moving_gc, bch_gc_wq);
 }
@@ -1857,7 +1830,7 @@ merged:
                                 op_type(op), pbtree(b), pkey(k));
 
         if (b->level && !KEY_OFFSET(k))
-                b->prio_blocked++;
+                btree_current_write(b)->prio_blocked++;
 
         pr_debug("%s for %s at %s: %s", status,
                  op_type(op), pbtree(b), pkey(k));
@@ -1907,7 +1880,6 @@ bool bch_btree_insert_check_key(struct btree *b, struct btree_op *op,
 
         BUG_ON(op->type != BTREE_INSERT);
         BUG_ON(!btree_insert_key(b, op, &tmp.k));
-        bch_btree_write(b, false, NULL);
         ret = true;
 out:
         downgrade_write(&b->lock);
@@ -1967,18 +1939,18 @@ static int btree_split(struct btree *b, struct btree_op *op)
                 bkey_copy_key(&n2->key, &b->key);
 
                 bch_keylist_add(&op->keys, &n2->key);
-                bch_btree_write(n2, true, op);
+                bch_btree_node_write(n2, &op->cl);
                 rw_unlock(true, n2);
         } else
                 bch_btree_insert_keys(n1, op);
 
         bch_keylist_add(&op->keys, &n1->key);
-        bch_btree_write(n1, true, op);
+        bch_btree_node_write(n1, &op->cl);
 
         if (n3) {
                 bkey_copy_key(&n3->key, &MAX_KEY);
                 bch_btree_insert_keys(n3, op);
-                bch_btree_write(n3, true, op);
+                bch_btree_node_write(n3, &op->cl);
 
                 closure_sync(&op->cl);
                 bch_btree_set_root(n3);
@@ -2082,8 +2054,12 @@ static int bch_btree_insert_recurse(struct btree *b, struct btree_op *op,
 
                 BUG_ON(write_block(b) != b->sets[b->nsets].data);
 
-                if (bch_btree_insert_keys(b, op))
-                        bch_btree_write(b, false, op);
+                if (bch_btree_insert_keys(b, op)) {
+                        if (!b->level)
+                                bch_btree_leaf_dirty(b, op);
+                        else
+                                bch_btree_node_write(b, &op->cl);
+                }
         }
 
         return 0;
diff --git a/drivers/md/bcache/btree.h b/drivers/md/bcache/btree.h
index af4a7092a28c..809bd77847a2 100644
--- a/drivers/md/bcache/btree.h
+++ b/drivers/md/bcache/btree.h
@@ -102,7 +102,6 @@
 #include "debug.h"
 
 struct btree_write {
-        struct closure          *owner;
         atomic_t                *journal;
 
         /* If btree_split() frees a btree node, it writes a new pointer to that
@@ -142,16 +141,12 @@ struct btree {
          */
         struct bset_tree        sets[MAX_BSETS];
 
-        /* Used to refcount bio splits, also protects b->bio */
+        /* For outstanding btree writes, used as a lock - protects write_idx */
         struct closure_with_waitlist    io;
 
-        /* Gets transferred to w->prio_blocked - see the comment there */
-        int                     prio_blocked;
-
         struct list_head        list;
         struct delayed_work     work;
 
-        uint64_t                io_start_time;
         struct btree_write      writes[2];
         struct bio              *bio;
 };
@@ -164,13 +159,11 @@ static inline void set_btree_node_ ## flag(struct btree *b)		\
 {       set_bit(BTREE_NODE_ ## flag, &b->flags); }                      \
 
 enum btree_flags {
-        BTREE_NODE_read_done,
         BTREE_NODE_io_error,
         BTREE_NODE_dirty,
         BTREE_NODE_write_idx,
 };
 
-BTREE_FLAG(read_done);
 BTREE_FLAG(io_error);
 BTREE_FLAG(dirty);
 BTREE_FLAG(write_idx);
@@ -293,9 +286,7 @@ static inline void rw_unlock(bool w, struct btree *b)
 #ifdef CONFIG_BCACHE_EDEBUG
         unsigned i;
 
-        if (w &&
-            b->key.ptr[0] &&
-            btree_node_read_done(b))
+        if (w && b->key.ptr[0])
                 for (i = 0; i <= b->nsets; i++)
                         bch_check_key_order(b, b->sets[i].data);
 #endif
@@ -370,9 +361,9 @@ static inline bool should_split(struct btree *b)
                  > btree_blocks(b));
 }
 
-void bch_btree_read_done(struct closure *);
-void bch_btree_read(struct btree *);
-void bch_btree_write(struct btree *b, bool now, struct btree_op *op);
+void bch_btree_node_read(struct btree *);
+void bch_btree_node_read_done(struct btree *);
+void bch_btree_node_write(struct btree *, struct closure *);
 
 void bch_cannibalize_unlock(struct cache_set *, struct closure *);
 void bch_btree_set_root(struct btree *);
diff --git a/drivers/md/bcache/debug.c b/drivers/md/bcache/debug.c
index 89fd5204924e..ae6096c6845d 100644
--- a/drivers/md/bcache/debug.c
+++ b/drivers/md/bcache/debug.c
@@ -144,7 +144,7 @@ void bch_btree_verify(struct btree *b, struct bset *new)
         v->written = 0;
         v->level = b->level;
 
-        bch_btree_read(v);
+        bch_btree_node_read(v);
         closure_wait_event(&v->io.wait, &cl,
                            atomic_read(&b->io.cl.remaining) == -1);
 
@@ -512,7 +512,7 @@ static ssize_t btree_fuzz(struct kobject *k, struct kobj_attribute *a,
 
                 bch_btree_sort(b);
                 fill->written = 0;
-                bch_btree_read_done(&fill->io.cl);
+                bch_btree_node_read_done(fill);
 
                 if (b->sets[0].data->keys != fill->sets[0].data->keys ||
                     memcmp(b->sets[0].data->start,
diff --git a/drivers/md/bcache/journal.c b/drivers/md/bcache/journal.c
index 8c8dfdcd9d4c..970d819d4350 100644
--- a/drivers/md/bcache/journal.c
+++ b/drivers/md/bcache/journal.c
@@ -384,7 +384,7 @@ out:
                 return;
 found:
         if (btree_node_dirty(best))
-                bch_btree_write(best, true, NULL);
+                bch_btree_node_write(best, NULL);
         rw_unlock(true, best);
 }
 
diff --git a/drivers/md/bcache/super.c b/drivers/md/bcache/super.c
index aaeda235fc75..e53f89988b08 100644
--- a/drivers/md/bcache/super.c
+++ b/drivers/md/bcache/super.c
@@ -1255,9 +1255,10 @@ static void cache_set_free(struct closure *cl)
         free_pages((unsigned long) c->uuids, ilog2(bucket_pages(c)));
         free_pages((unsigned long) c->sort, ilog2(bucket_pages(c)));
 
-        kfree(c->fill_iter);
         if (c->bio_split)
                 bioset_free(c->bio_split);
+        if (c->fill_iter)
+                mempool_destroy(c->fill_iter);
         if (c->bio_meta)
                 mempool_destroy(c->bio_meta);
         if (c->search)
@@ -1295,7 +1296,7 @@ static void cache_set_flush(struct closure *cl)
         /* Should skip this if we're unregistering because of an error */
         list_for_each_entry(b, &c->btree_cache, list)
                 if (btree_node_dirty(b))
-                        bch_btree_write(b, true, NULL);
+                        bch_btree_node_write(b, NULL);
 
         closure_return(cl);
 }
@@ -1374,7 +1375,6 @@ struct cache_set *bch_cache_set_alloc(struct cache_sb *sb)
                                        BTREE_MAX_PAGES);
 
         mutex_init(&c->bucket_lock);
-        mutex_init(&c->fill_lock);
         mutex_init(&c->sort_lock);
         spin_lock_init(&c->sort_time_lock);
         closure_init_unlocked(&c->sb_write);
@@ -1400,8 +1400,8 @@ struct cache_set *bch_cache_set_alloc(struct cache_sb *sb)
             !(c->bio_meta = mempool_create_kmalloc_pool(2,
                                 sizeof(struct bbio) + sizeof(struct bio_vec) *
                                 bucket_pages(c))) ||
+            !(c->fill_iter = mempool_create_kmalloc_pool(1, iter_size)) ||
             !(c->bio_split = bioset_create(4, offsetof(struct bbio, bio))) ||
-            !(c->fill_iter = kmalloc(iter_size, GFP_KERNEL)) ||
             !(c->sort = alloc_bucket_pages(GFP_KERNEL, c)) ||
             !(c->uuids = alloc_bucket_pages(GFP_KERNEL, c)) ||
             bch_journal_alloc(c) ||
@@ -1409,8 +1409,6 @@ struct cache_set *bch_cache_set_alloc(struct cache_sb *sb)
             bch_open_buckets_alloc(c))
                 goto err;
 
-        c->fill_iter->size = sb->bucket_size / sb->block_size;
-
         c->congested_read_threshold_us  = 2000;
         c->congested_write_threshold_us = 20000;
         c->error_limit  = 8 << IO_ERROR_SHIFT;
@@ -1551,7 +1549,7 @@ static void run_cache_set(struct cache_set *c)
                         goto err_unlock_gc;
 
                 bkey_copy_key(&c->root->key, &MAX_KEY);
-                bch_btree_write(c->root, true, &op);
+                bch_btree_node_write(c->root, &op.cl);
 
                 bch_btree_set_root(c->root);
                 rw_unlock(true, c->root);